Precision leveling chuck



Aug, 24, 1948. 4 E, MlKls 2,447,711

l PRECISION LEVELING CHUCK Filed Jan. 16, 1946 I 2 Sheets-Sheet 1' 72 1N TOR; y F7@ 2 4 EKA/55T H05 H/5 ATTORNEY Aug. 24, 1948. E. MIKls 2,447,711

PRECISION LEVELING CHUCK Filed Jan. 16, 1946 2 sheets-sheet 2 IN VEN TOR. Cm/55T MVK/5 Patented Aug. 24, 1948 iwliilTED S'ATEH..

vorifice This .invention relates Ito chucks of the 'type commonly employed for work holding purposes and is concerned primarily with a chuck having precision leveling features.

At the present time the use of the conventional four-jaw chuck lor work holding purposes in the many metal. working machines dui-te prei/14 alent. The ordinary lathe chuck may be taken as vtypical and such a chuck generally includes four jaws, each of which is individually adjustm able with respect to the jaw holder so .that accurate ladjustment of the work held between the jaws is fea-sible. However, the adjustment provided by the now known chuck of this type is limited to a single p-lane. Thus, while it is possible to accurately position a 'piece of work with respect to the working center of the lathe there are times when the axis of the work will not truly .align with .the axis of the lathe. If this discrepancy exists, it will, of course, show up in the ultimate product which is a highly undesirable condition..

With these factors in mind this invention has in view as its foremost objective the provision of a chuck of the character labove noted which includes means separate and independent from t'he individual adjustment ofthe work holding jaws pron viding for adjustment of the axis of the work with respect .to the working center of the machine .in which the chuck is used. In carrying yout this idea in a practical embodiment the invention pron poses an arrangement in which the jaw holder has associated therewith instrumentalities for adjusting it as .a complete assembly in aplane which 'it ordinarily assumes substantially normal to the working center lof the machine. Thus, Ythe postion of the jaw holder is tilted, as occasion demands, with respect to the working axis of the machine.

A. chuck of the type with which this invention is concerned ordinarily includes a main chuck body carrying a ball on which Ithe jaw holder is operatively mounted. A further more detailed object of this invention is the provision in such a chuck of means for adjusting the jaw holder with respect to Ithe chuck body.

Still more in detail, ythe invention has as an object .the provision, in a chuck y.of the type indicated, of a screw actuated wedge device for adjusting the position of the jaw holder with respect to' the chuck body. In carrying out this idea the jaw holder is formed with a series of tracks, each ci' which receives one element of a wedge device. Substantially opposite to each of these tracks and formed in the chuck body are cylindrical openings, each of which receives a screw actuator, the latter engages with the second element of the wedge device that is pivotly joined to the first element. .as the screw actuators are operated to move the.

wedge elements which mesh therewith, .the entire wedge assembly is moved to cause adjustment of the jaw holders with respect to the chuck body. It is important to note that the tracks in the jaw` holder .are inclined with respect `to the cylindrical openings in the 'chuck body, thus providing the` relative adjustment under the influence of `the wedge assemblies.

Various other more detailed objects and ad,- vantages of the invention such as larise in connection with carrying out the above noted thoughts in a practical embodiment will in part become ap-` .parent and in part be hereinafter stated as a description of the invention proceeds.

The invention, therefore, comprises a precision leveling chuck consisting of 'a chuck body having a ball on which is adjustably mounted a jaw holder. The usual 'work holding paws are mounted for individual adjustment in the paw holder and wedge devices operatively associ-ated with .the chuck body and jaw holder provide for the adjustment of the latter by `tilting the position 'of complete jaw holder assembly as a plane substann tially normal to the working center of the ma chine in which the chuck is used.

For a full and more complete understanding of theinvention reference may be had to the following ,description and laccompanying drawings wherein:

Figure l is a front view of a precision leveling chuck embodying the precepts of this invention. In this view parte are broken away to more cleanly illustrate parts that would ordinarily be concealed and other parts are shown in dotted lines.

Fig. 2 is a top plan View oi the chuck shown in Fig. l.

Fig. 3 is a transverse section taken about on the plane represented by the line 3 3 of Fig. 1 and Fig. l is an enlarged detailed perspective of one of the wedge assemblies.

Referring now to theY drawings wherein' like rcierencecharac-ters denote corresponding parts', and firs-t more particularly 4to Fig. the improved chuck of this invention is shown as comprising a main chuck body B and a jaw holder identied in its entirety by .the reference character H.

Upon referring toiiig. 8 it will be noted that the chuck body B includes van inner threaded shank I@ which may be utilized in assembling the chuck on. a metal working machine such as a lathe. Carried by the shank lil is a circular member l l that is formed with a central cup-like recess I2 which receives the base I3 of a ball I4. It will be noted that the `parts I2, I3, and I4 are formed with aligned bores which communicate with the threaded passage in the shank Il] and consti-tute substantially `a continuation thereof. The base I3 may be secured in the recess I2 of the plate II in any preferred manner as by the screw fastening elements shown at I '5.

The circular plate II i-s provided with a suitable number of radially extending cylindrical passages I6 which open at the front into slots I 'I. Any desired number of the passages I6 may be provided. Inasmuch as the chuck illustrated and herein described is a four-jawed chuck it is shown as including four of the passages I6 which are equiangularly spaced apart, thus providing for one of these passages every ninety degrees. Obviously the invention is not to be limited to just this particular number as it may be varied without departing from the spirit of the invention.

The jaw holder H is of a circular plate-like formation corresponding to the plate II and is enlarged centrally a-s clearly shown in Figs. 2 and 3. This center portion is formed with a recess I8 which is complemental to the outer spherical surface of the ball I4 which is received therein. A retaining ring I9 which may be anchored in any preferred manner to the jaw holder H as by screw 2l) serves to maintain the assembled relation of the jaw holder on the spherical member I4.

Referring now more particularly to Fig. 1, the jaw holder H is shown as being formed with a plurality, in this instance four, radially extending slots 2I, and in each slot 2| there is positioned a work holding jaw 22. The outer ends of the slots 2I may be threaded as depicted at 23 to provide for the individual adjustment of each jaw 22. The particular manner in which each jaw 22 is adjusted is not a part of this invention. Fourjawed chucks of this type are well-known and they provide the means for adjusting each jaw individually.

Disposed opposite to the slots I'I of passages I6 and substantially midway between each pair of slots 2I in jaw holder H are tracks 24 which are inclined at an angle with respect to the face 25 which is substantially normal to the axis of the chuck as an entirety. The passages I6 and slots I1 are similarly inclined in a reverse direction and at substantially the same angle of inclination with respect to the face 26 of the plate II which is also substantially normal to the axis of the chuck.

There are four of the tracks 24 that are spaced ninety degrees apart and each of these tracks is substantially forty-five degrees from the adjacent slots 2|. Each of the slots 24 opens on the rear face into a slot 21 which confronts the slot I'I of the opposite passage I6.

Referring now more particularly to Fig. 4, a wedge assembly is referred to in its entirety by the reference character W. The assembly W cornprises a member 28 that is received in one of the tracks 24 and which is complemental in shape with respect thereto so as to slide snugly therealong and this member or plunger 28 is formed with an ear 29 that is thinned at 30 where it passes through the slot 21. A slide 3|' is positioned in the slot I1 and extends into the passage I6 wherein it has a concave face in the form of a segment of a cylinder. This face is designated 32 and is threaded as indicated at 33. Connected to the element 3| is a neck 34 that carries a pair of spaced ears 35 which receive therebetween the ear 29. The ears 29 and 35 are formed with aligned openings through which passes a pivot pin 36. This establishes a pivotal relation between the slide 3I and the plunger 28.

Mounted on each passage I 5 is a screw actuator 3l having threads meshing with the threaded face 33. It will be noted that the actuator'Bl may be held against longitudinal movement in the respective passage I6 in any preferred manner such as by a stud 38 which cooperates with an interruption in the threads 3l. The outer end of each actuator 3l is provided with a non-circular socket such as the square recess shown at 39 in Fig. 2 for wrench engaging purposes.

While the operation of the above described mechanism is believed to be obvious, it may be briefly outlined by noting that a piece of work such as e, cylindrical shaft i-s rst inserted into a position in which it will be engaged by the jaws 22 upon the relative contraction thereof. By properly adjusting these jaws the work may be brought so that its axis substantially coincides with the work center of the machine in which the chuck is used. However, should the axis of this piece of work be out of alignment with the working axis of the machine the jaw holder H may be adjusted as an entirety to bring these two axes into accurate coincidence. This is accomplished by employing a socket wrench in conjunction with the sockets 39 of the screw actuators 31. Thus, each wedge assembly W may be moved up or down a-s occasion requires to adjust the plane of the face 25 with respect to the Working axis. This in turn adjusts the axis of the work held by the jaws 22 to bring it into the desired alignment.

While a preferred specic embodiment of the invention is hereinbefore set forth, it is to be clearly understood that the invention is not to be limited to the exact construction illustrated and described because various modifications of these details may be provided in putting the invention into practice within the purview of the appended claims.

What is claimed is:

1. In a chuck of the character described, a chuck body consisting of a circular plate formed with a central recess, said body being formed with a radially extending passage opening into a slot on one face of the body, a ball element carried by said chuck body, a jaw holder mounted on said ball element, a plurality of work holding jaws carried on said jaw holder, said jaw holder being formed with a track substantially opposite to said passage, there being a `slot opening from said track into the rear Iof said jaw holder opposite to the slot in said chuck body, said passage and track being inclined with respect to each other, a wedge assembly mounted in said passage and track, and mean-s to actuate said wedge assembly to cause relative adjustment of said jaw holder and chuck body.

2. In a precision leveling chuck of the character described, adjusting mechanism comprising a wedge assembly including a plunger adapted to be mounted in a track in a jaw holder, a slide adapted to be mounted in a passage in a chuck body, a pivotal connection between said plunger and slide, and screw means for actuating said Wedge assembly.

3. In a chuck of the character described, a shank for securing said chuck in position in a metal working machine, a circular chuck body carried by said shank and formed with a plurality of passages equiangularly spaced apart, a ball element carried by said chuck body, a jaw holder having a shape corresponding generally to the shape -of said chuck body and mounted on said ball element for adjustment with respect to said chuck body, a plurality of Work holding jaws adjustably mounted in said jaw holder, said jaw holder being formed with a plurality of tracks corresponding in number and position to the passages in said chuck body, a wedge assembly cooperating with each pair of passage and track, and a screw actuator in said chuck body cooperating with each wedge assembly to actuate the latter.

4. In a precision leveling chuck, a jaw holder formed with four slots, four radially extending slots spaced ninety degrees apart, an adjustable Work holding jaw in each slot, said jaw holder being formed With four radially extending tracks spaced ninety degrees apart with each track being disposed midway between each pair of slots, a chuck body, a ball element carried by said chuck body and adjustably supporting said jaw holder, said chuck body being formed with four REFERENCES CITED The following references are of record in the iile of this patent:

UNITED STATES PATENTS Number Name Date 1,222,466 Railton Apr. 10, 1917 FOREIGN PATENTS 20 Number Country Date 96,-510 Switzerland Oct. 16, 1922 18,034 Great Britain Aug. 27, 1908 

